Efficacy of naltrexone and acamprosate for alcoholism treatment: a meta-analysis

Renewed interest in medications to prevent relapse in alcoholics (i.e., antidipsotropics) resulted in approval by the Food and Drug Administration of naltrexone to treat alcohol dependence. Acamprosate, although not approved in the United States, is used in alcoholism treatment in many other parts of the world. In the absence of studies that compare the effects of these medications, we used a meta-analytic approach to the literature to compare their efficacy in alcoholism treatment.

All published placebo-controlled trials of naltrexone or acamprosate for alcohol dependence were examined, and, when suitable, data were extracted for calculation of a mean effect size. A sample of studies of selective serotonin reuptake inhibitors for treatment of major depression conducted over the last two decades served as a comparator for the antidipsotropics.

Both antidipsotropics exerted significant, but modest, effects on treatment retention and/or drinking outcomes. There was significant variability among the studies for the measure on which the largest effect was exerted by each of these medications. Based on limited comparisons of the two medications, there appears to be no statistical difference in their efficacy in the treatment of alcohol dependence. In contrast, there was a consistent effect of selective serotonin reuptake inhibitors on depressive symptoms in major depression, which was significantly greater than the effects observed for the antidipsotropics.

Both naltrexone and acamprosate are efficacious in reducing alcohol consumption in alcoholics. However, their specific role in alcoholism treatment remains to be more clearly defined. New approaches to the use of these medications and development of new medications are needed if pharmacotherapy is to play a substantial role in the treatment of alcoholism.